Leone Buckle: To what extent does the form of speech input facilitate grammar learning?
Children often repeat the words and sentence structures used by their partner within conversations and over time, their vocabulary and grammatical development reflects the diversity and complexity of their language input. This talk will highlight research conducted as part of the Language Experience and Development (LEaD) project which investigates the nature of children’s experience-based language learning in various contexts. More specifically, I will discuss how children’s experiences with language input across different modalities can facilitate their sentence production over the course of development. I will first consider how children’s immediate experiences with language during in-person interactions can lead to long-term grammar learning. Nevertheless, many children have experienced a lack of in-person interactions and an increase in online input during the COVID-19 pandemic. It is thus important to assess whether the nature of an interaction affects children’s propensity to learn from that interaction. Earlier research suggests that there is a video deficit whereby children show decreased learning rates from videos as compared to in-person demonstrations. Socially contingent interactions via live video chats have been shown to improve the deficit and children’s tendency to learn from both live and pre-recorded videos appears to increase with age. However, these findings have largely been obtained from studies on word learning. The focus of this talk will therefore be on a new study exploring children’s propensity to learn grammar from different forms of input (audio+video vs audio-only) during online interactions. This syntactic priming study investigated the extent to which children at early and later stages of acquiring the passive construction use passives in their own sentences immediately after hearing their partner use them. I will discuss the study’s theoretical implications as well as methodological considerations for the use of online priming experiments to study children’s language learning.

Caroline Rowland: What predicts how quickly children learn to talk?
There are large individual differences in the speed with which children acquire language in the early years. A popular approach is to attribute this variance to differences in the quality and quantity of the child’s interactions and input; for example, to the amount of child directed speech or the number of conversational turns that adults and children use in interaction. However, even the strongest findings report only small to moderate effect sizes of linguistic input. In recent years we’ve been applying a constructivist approach to explaining individual variation to see how far it can take us. In this approach, language development is conceptualized as emerging from rich pre-linguistic communicative and cognitive abilities, with individual learning trajectories being shaped by interactions between environmental input, the child’s current knowledge, and the child’s learning and processing mechanisms. In this talk I illustrate some of our findings from this approach, using data from the longitudinal Language 0-5 Project, in which we followed 90 children from 6 months to 4 and a half years old, and assessed the impact of a range of socio-cognitive, cognitive, and environmental factors on individual differences in language growth.

Courtenay Norbury: Gesture use in parents and children with (and without) developmental language disorder.
In young typically developing children, direct and indirect relationships between parent gesture, child gesture and child language acquisition have been observed. Far less is known about these relationships in atypical language development. In a series of studies, we investigated the nature of gestures in parent–child dyads for children aged 6–8 years with developmental language disorder (DLD: n = 21) relative to parents of typically developing peers (TD: n = 18) and children with low language (LL) and educational concerns (n = 21). Parents of children with DLD gestured at significantly higher rates than parents of TD children, but only during a complex interactive problem solving task. Across the entire sample, parent gesture rate was positively correlated with child gesture rate, but negatively correlated with child vocabulary. In addition, parents of children with DLD were more likely to verbally translate child gestures, and this too was negatively correlated with child language. Gesture may serve as a strategy to maximise communication success for children with language difficulties and is most evident when communication demands are high.

Aparna Nadig: Linguistic input to children on the autism spectrum in a multilingual society: Relationships between quantity and quality of input and child language development.
Children on the autism spectrum have highly varied language profiles, with 40% exhibiting language in the normal range or mild delays, an additional 30% exhibiting significant language delays (Pickles et al., 2014), and approximately 30% having little to no functional spoken language (Bal et al., 2016). Since many children on the spectrum face significant communication challenges, on the surface they appear not to benefit from language input in their environment in the same way as typically-developing children. Moreover, given that reduced early social attention is a defining feature of autism (APA, 2013), and that reduced attention to child-directed speech has been reported (see Filipe et al., 2018 for a review), learning from the input may not necessarily be expected.
In Part 1 of the talk I will review work from my and others’ labs on the nature of the language learning environment, or input, available to toddlers and preschoolers on the spectrum, relative to that of typically developing children. I will also present evidence indicating that children on the spectrum, as a group, do in fact make use of the language they hear, and benefit from lexically rich and syntactically complex input, as do typically developing children. Differences in input, therefore, may help explain part of the tremendous variability observed in their language development trajectories.
The aforementioned social and communication challenges lead to a commonly held belief that bilingualism could further delay language development in children on the spectrum; yet a body of research demonstrates that there is no such additional delay (see Drysdale et al. 2015 for a review). In Part 2 of the talk I review evidence showing that children on the spectrum can become proficiently bilingual when adequate language exposure is provided. Furthermore, the amount of exposure to a language has a strong, positive relationship with a child’s vocabulary and morphological skills at school-age, as it does in typical development (Gonzalez Barrero and Nadig 2018).

Danielle Matthews: Learning to communicate through interaction in infancy.
This talk will trace the early steps of pragmatic development in human infants, from a dyadic phase, through to intentional triadic communication, early word use and later developments that support adult-like inferences. The focus will be on exploring the role of learning from experience in order to make these transitions. Evidence will be provided from the study of individual differences, from randomised controlled trials and from deaf infants growing up in families with little prior experience of deafness (and who are thus at risk of reduced access to interaction).

Liz Nilsen: Children’s use of a communicative partner’s perspective when generating, repairing, and interpreting statements.
Adaptation within our social world requires the ability to effectively communicate with others. To be successful, communicators are required to simultaneously track social, linguistic, and contextual information – and manage the flow of information between themselves and their conversational partners. In particular, effective communication requires that conversational partners be attuned to each other’s mental states to adequately produce and comprehend statements, and to do so in an efficient manner. Indeed, it has been argued that no social activity requires more negotiation with the minds of others than conversation (Malle & Hodges, 2007). In this talk, children’s communicative perspective-taking, that is, the ability to use the perspective of one’s conversational partner to guide communicative behaviour, will be discussed in the context of a theoretical model outlining the developmental prerequisites that support successful communicative behaviours (Nilsen & Fecica, 2011). More specifically, findings from studies where children are in the role of speakers (i.e., producing and repairing statements), as well as listeners (i.e., interpreting others’ statements) will be highlighted. An analysis of the cognitive skills associated with these abilities will be provided, noting complexities and limitations in this field of work. Finally, implications for broader social functioning as well as for specific populations of children will be highlighted.